Hearing aid



FIG. 1 is a front elevational view of a hearing aid showing my new design;

FIG. 2 is a rear elevational view thereof;

FIG. 3 is an enlarged left side view thereof;

FIG. 4 is an enlarged right side view thereof;

FIG. 5 is a top plan view thereof;

FIG. 6 is a bottom plan view thereof;

FIG. 7 is a perspective view thereof;

FIG. 8 is another perspective view thereof; and,

FIG. 9 is a perspective view thereof in state of use.

The broken lines in FIG. 9 represent an environment, and the broken lines in FIG. 3 depict a portion of the hearing aid that forms no part of the claimed design. The broken lines form no part of the claimed design. 

CLAIM The ornamental design for a hearing aid, as shown and described. 